| /* |
| * Copyright 2014, NICTA |
| * |
| * This software may be distributed and modified according to the terms of |
| * the BSD 2-Clause license. Note that NO WARRANTY is provided. |
| * See "LICENSE_BSD2.txt" for details. |
| * |
| * @TAG(NICTA_BSD) |
| */ |
| |
| |
| /** |
| * The IRQ server helps to manage the IRQs in a system. There are 3 API levels |
| * in the design |
| * 1. [irq server node] The IRQ server node is a set of IRQs and their |
| * associated handlers. It is a passive system, hence, |
| * the application is responsible for waiting on the |
| * appropriate notification endpoint for events. |
| * The AEP binding feature of the seL4 kernel may be used |
| * here to listen to both synchronous IPC and IRQ |
| * notification events. |
| * 2. [irq server thread] An IRQ server node is a standalone thread which waits |
| * for the arrival of any IRQ that is being managed by a |
| * particular irq server node. When an IRQ is received, |
| * the irq server thread will either forward the irq |
| * information to a registered synchronous endpoint, or |
| * call the appropriate handler function directly. |
| * 3. [irq server] A dynamic collection of server threads. When |
| * registering an IRQ call back function, the irq server |
| * will attempt to deligate the IRQ to an irq server node |
| * that has not yet reached capacity. If no node can accept |
| * the IRQ, a new irq server thread will be created to |
| * support the additional demand. |
| * |
| * ++ Special notes ++ |
| * |
| * Performance |
| * The application can achieve greater performance by configuring the irq server, |
| * or irq server threads, to call the IRQ handler functions directly. In this |
| * case, the application must take care to ensure that all concurrency issues are |
| * addressed. |
| * |
| * Resource availability |
| * The irq server API family accept resource allocators as arguments to some |
| * function calls. In a dynamic system design, these resource allocators |
| * must be kept available indefinitely, or until the system reaches a known |
| * steady state. |
| */ |
| |
| #ifndef SEL4UTILS_IRQ_SERVER_H |
| #define SEL4UTILS_IRQ_SERVER_H |
| |
| #include <autoconf.h> |
| |
| #if (defined CONFIG_LIB_SEL4_VKA && defined CONFIG_LIB_SEL4_VSPACE && defined CONFIG_LIB_SEL4_SIMPLE) |
| |
| #include <sel4/sel4.h> |
| #include <vspace/vspace.h> |
| #include <vka/vka.h> |
| #include <simple/simple.h> |
| |
| |
| typedef int irq_t; |
| |
| struct irq_data; |
| |
| /** |
| * @return non-zero if the IRQ should be ACKed |
| */ |
| typedef void (*irq_handler_fn)(struct irq_data* irq); |
| |
| struct irq_data { |
| /// irq number |
| irq_t irq; |
| /// The capability for this irq number |
| seL4_CPtr cap; |
| /// Client data: function to call when the IRQ arrives |
| irq_handler_fn cb; |
| /// Client specific handle to pass to the callback function |
| void* token; |
| }; |
| |
| /** |
| * Allows a client to acknowledge an IRQ |
| * @param[in] irq The IRQ to acknowledge |
| */ |
| void irq_data_ack_irq(struct irq_data* irq); |
| |
| |
| /********************************* |
| *** IRQ server node functions *** |
| *********************************/ |
| |
| typedef struct irq_server_node* irq_server_node_t; |
| |
| /** |
| * Create a new IRQ server node. |
| * @param[in] aep An async endpoint that can be used for binding IRQ notification |
| * @param[in] badge_mask A mask for the available badge. Bits NOT set in the mask are |
| * considered reserved and will not be used for IRQ identification. |
| * This does, however, reduce the number of IRQs that this node can |
| * manage. One may choose to reserve badge bits for the |
| * identification of other notifications to the same endpoint. |
| * @return A handle to the created IRQ server node, or NULL on failure. |
| */ |
| irq_server_node_t irq_server_node_new(seL4_CPtr aep, seL4_Word badge_mask); |
| |
| /** |
| * Register an IRQ with a server node. |
| * @param[in] n The irq server node to register the IRQ with. |
| * @param[in] irq The IRQ number of the IRQ to be registered |
| * @param[in] cb A callback function to be called when the IRQ event occurs |
| * @param[in] token A token to be passed, unmodified, to te callback function |
| * @param[in] vka An allocator for for kernel objects |
| * @param[in] cspace The current capability space |
| * @param[in] simple A simple interface for creating the irq handler |
| * @return A handle to the irq structure that was created. |
| */ |
| struct irq_data* irq_server_node_register_irq(irq_server_node_t n, irq_t irq, |
| irq_handler_fn cb, void* token, |
| vka_t* vka, seL4_CPtr cspace, |
| simple_t* simple); |
| |
| /**************************** |
| *** IRQ server functions *** |
| ****************************/ |
| |
| typedef struct irq_server* irq_server_t; |
| |
| /** |
| * Initialises an IRQ server. |
| * The server will spawn threads to handle incoming IRQs. The function of the |
| * threads is to IPC the provided synchronous enpoint with IRQ information. When the IPC |
| * arrives, the application should call \ref{irq_server_handle_irq_ipc} while IPC |
| * registers are still valid. \ref{irq_server_handle_irq_ipc} will decode the provided |
| * information and redirect control to the appropriate IRQ handler. |
| * @param[in] vspace The current vspace |
| * @param[in] vka Allocator for creating kernel objects. If the server is |
| * configured to support a dynamic number of irqs, this |
| * resource allocator must remain available until the system |
| * reaches a steady state. |
| * @param[in] cspace The cspace of the current thread |
| * @param[in] priority The priority of spawned threads. |
| * @param[in] simple A simple interface for creating IRQ caps |
| * @param[in] sync_ep The synchronous endpoint to send IRQ's to |
| * @param[in] label A label to use when sending a synchronous IPC |
| * @param[in] nirqs The maximum number of irqs to support. |
| * -1 will set up a dynamic system, however, the |
| * approriate resource managers must remain valid for |
| * the life of the server. |
| * @param[out] irq_server An IRQ server structure to initialise. |
| * @return 0 on success |
| */ |
| int irq_server_new(vspace_t* vspace, vka_t* vka, seL4_CPtr cspace, seL4_Word priority, |
| simple_t *simple, seL4_CPtr sync_ep, seL4_Word label, |
| int nirqs, irq_server_t* irq_server); |
| |
| /** |
| * Enable an IRQ and register a callback function |
| * @param[in] irq_server The IRQ server which shall be responsible for the IRQ. |
| * @param[in] irq The IRQ number to register for |
| * @param[in] cb A callback function to call when the requested IRQ arrives. |
| * @param[in] token Client data which should be passed to the registered call |
| * back function. |
| * @return On success, returns a handle to the irq data. Otherwise, |
| * returns NULL |
| */ |
| struct irq_data* irq_server_register_irq(irq_server_t irq_server, irq_t irq, |
| irq_handler_fn cb, void* token); |
| |
| /** |
| * Redirects control to the IRQ subsystem to process an arriving IRQ. |
| * The server will read the appropriate message registers to retrieve the |
| * information that it needs. |
| * @param[in] irq_server The IRQ server which is responsible for the received IRQ. |
| */ |
| void irq_server_handle_irq_ipc(irq_server_t irq_server); |
| |
| #endif /* (defined CONFIG_LIB_SEL4_VKA && defined CONFIG_LIB_SEL4_VSPACE) */ |
| #endif /* SEL4UTILS_IRQ_SERVER_H */ |
